This invention relates to the field of air conditioning and heating exchanger interflow for aiding the heating and cooling of a building.
A number of patents disclose various methods of circulating the waste heat from a heater for the purpose of more efficient use of heat in a building.
Soviet Patent 759,803 discloses the use of porous inserts for ventilators within a building so as to remove the heat from air exhausted from the building and add it to external air being brought in.
British Pat. No. 1,337,396 discloses, incident to a heating system which involves the use of extraordinarily long runs of ducting to heat the seats in a stadium, using the radiant lost heat from the ducting as part of the overall heating effect.
U.S. Pat. No. 3,247,895 to Phillips discloses ducting hot or cold air through a building by sealing the inner space between the walls and the floors and utilizing the resulting air space as an air duct. A related concept can be shown in U.S. Pat. No. 2,240,951 to Hamjy and U.S. Pat. No. 3,905,548 to Brodie. Japanese Pat. No. 57-131948 discloses a variation of this concept, using a rising duct pipe with a thermostatically activated ventilator system to inject air into the attic area of a house, displacing the warmer air into the walls, so as to more effectively conduct the heat of the attic to the rooms of the building.
U.S. Pat. No. 3,727,538 to Jacobson and U.S. Pat. No. 2,669,393 to Schleicher are alternate forms of heating systems.
In addition to the Japanese patent noted above, U.S. Pat. No. 2,700,331 to Miller discloses the use of the entrapped heated air within an attic space in a dual purpose air circulating unit, substituting for the standard ventilator wind turbine, which can either exhaust the hot air for a cooling effect or alternatively, blow the hot air in a downward direction too more evenly distribute the heat if a heating effect is desired.
SUMMARY OF THE INVENTION
This invention relates to an apparatus for utilizing the air flow from an external heat exchanger of a standard household air conditioning unit to reduce the total heat loading on a building in the summer.
In its simplest forms, the apparatus comprises a large, open ended air collector attachment above an external heat exchanger of a standard residential air conditioner, which ducts the exhausted heat exchanger air flow into the attic of a building through a substantially vertically ascending air flow tube.
In use, the device takes advantage of the fact that each standard air-conditioning unit has a vertical exhaust fan driving hot air from the heat exchanger. Part of this hot air flow is captured within an air collector and directed into an ascending air tube. The continuous ascending air tube preserves the heat induced air flow; the flow rate in the air tube is enhanced through a chimney draft effect (adiabatic expansion lifting) since the exhaust air from the heat exchanger of the air conditioner is above ambient temperature.
Intuitively, pumping hot air into the attic of the building would seem to be counterproductive for cooling. In fact, it has been determined through experimentation that the combination of the fan exhaust pressure together with adiabatic expansion of the air rising in the air tube produces sufficient air flow within the attic to pressure ventilate and further cool an average household attic.
It has been determined through experimentation that air trapped within a building attic in a summertime environment is heated to a temperature greater than the air exhausted from the heat exchanger of an average household air-conditioning unit. Thus, this exchange of air, under positive pressure, significantly lowers the overall air temperature within the attic.
This, in turn, reduces the heat load into the air-conditioned spaces of the house, by reducing the heat radiated from the attic spaces downward through the ceiling of the house.
The apparatus provides more efficiency in ventilating the attic than a wind turbine or power driven attic fan, at a significant saving in energy costs because of its re-use and recycling of otherwise waste heat and exhaust air from the air-conditioner.
It is therefore, an object of this invention to disclose an apparatus for addition to a standard air conditioning installation which reduces the total heat loading on a building.
It is a further object of this invention to disclose an apparatus for use in conjunction with a standard air conditioner installation which increases the efficiency of cooling of the overall air conditioning system.
It is a further object of this invention to disclose an apparatus which reduces substantially the temperature loading of a building which is air conditioned.